When a person loses sphincter control, intervention with some sort of rectal, continence control appliance is often employed. Creating a seal around the anus such that the seal is dependable and conducive to body tissue is important for the function of continence control devices. Once this seal has been made, a variety of techniques may be employed for containing, collecting and/or controlling stool. Some current devices rely on adhesives to attempt to create a seal between the appliance and the anus. However, an adhesive seal can affect, and can be affected by, the wearer's mobility. Should the adhesive seal fail, then the wearer may be exposed to uncontrolled discharge of stool. Other devices use an expandable balloon or other expandable member to form a single seal against the inside of the body opening, or may use plastic or other materials to form a rigid shape for insertion. Again, such seals can affect, and can be affected by, the wearer's mobility. Also, such devices have to be designed carefully to avoid the risk of damage to the sensitive internal tissue. A relatively high concentration of force may result on the tissue underneath the body opening, especially when the external surface or stop is of limited conformability.
By way of example, reference is made to JP-A-9253112 which describes a rectal appliance with a discharge tube carrying internally fitting and externally fitting inflatable balloons. Such a device may reduce the risk of tissue damage by using inflatable balloons internally and externally of the anus to sandwich the anus. However, the device is bulky, which may make it impractical to wear for extended periods, or under normal clothing. For example, the size and shape of the external balloon is extremely prohibitive without benefiting the seal performance.
U.S. Pat. No. 4,686,985 describes an anal dilator and occluder also including internally fitting and externally fitting inflatable balloons. The device has an asymmetric shape suited to the shape of the anus. However, the device is merely an occluding plug and does not permit any discharge of stool when in position. The device has to be removed in order to defacate. Not only is this inconvenient, but it also involves frequent handling of the device which is potentially unhygienic.